Trelino Evo S Portable Composting Toilet review – This travel toilet is number one for number two (and number one)!

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REVIEW – Spending any significant amount of time living outdoors requires a lot of equipment, planning, and special considerations. One of the most important things to plan for is what’s known as “the bathroom situation.” Every time I invite someone along on an outdoor adventure lasting more than a day, the question I’m most asked is “So, what’s the bathroom situation?” Usually, I’ll answer with a snarky, “Bring a shovel and an open mind,” but now I have a better option.

The Trelino Evo S Portable Composting Toilet has changed the way my troupe and I “go” outdoors. Costing a pricey $399, the uniquely designed toilet is a far cry from a $10 bucket with a seat, but it’s worth it when taking into account the clever waste separation, the smell mitigating design, and its build quality. There are definitely cheaper options out there, but after using the Trelino Evo S, I’m ready to ditch my shovel.

What is it?

The Trelino Evo S is a German-made, lightweight, and compact outdoor toilet designed for waste management during outdoor adventures. It features a urine canister with a volume of 1.2 gallons and a solid waste container with a volume of 1.6 gallons. The Trelino Evo S utilizes biodegradable waste bags and your choice of litter to dry out solid waste to prevent odors.

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The Trelino Evo S ships safely in a plain brown cardboard box with bubble wrap protecting it during transport.

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What’s included?

  • Exterior toilet body
  • Seat with urine separator and soft closing lid
  • Solid waste container (1.6 gal)
    • Closed lid for waste container
  • Urine canister (1.2 gal)
    • Lid with membrane closure
    • Closed lid for urine canister
  • Biodegradable waste bags‎
  • User manual

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Tech specs

  • Materials: ABS and polypropylene plastic
  • Dimensions:
    • Width: 13″
    • Height: 11.7″
    • Depth: 15.4″
  • Emptying cycle: 1 – 2 days depending on usage
  • Urine capacity: 1.2 gal (9 – 11x)
  • Solids capacity: 1.6 gal (4 – 8x)
  • Weight: 8.6lbs
  • Weight limit: 330lbs

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Design and features

The main draw of the Trelino Evo S composting toilet is the simple design of the exterior and the unique system for handling solid and liquid waste. Basically, by utilizing a litter medium for solid waste and separating it from liquid waste, the formation of odors is effectively prevented. Also, by avoiding the use of chemicals and water, it’s a lot simpler to empty than similar travel toilets.

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The Trelino EVO’s body and lid are made of slightly textured ABS plastic, while the interior containers are constructed from polypropylene. Both are made from recyclable materials and are resistant to aqueous chemicals. At 8.6 lbs empty, the Trelino Evo S is also very easy to transport.

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The front of the Trelino has very simple branding with a subtle Trelino logo on the top.

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Along the back of the EVO is the hinge of the unit’s lid. The Trelino logo is featured on the back as well.

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A slight notch under the front of the lid allows for easy lifting when nature calls. The lid has an automatic soft close feature, which is a great addition to avoid making noise during late night visits.

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Inside the lid is another EVO logo and a smoother textured ABS surface.

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On either side of the EVO are notches that make it easier to pick up and carry, especially if it’s filled.

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The seat is nicely contoured for comfort, but might be a bit small for larger users. The rear section for solid waste is separated from the front drain for liquid waste by a curved lip.

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The drain hole for liquid waste is centered in the front portion of the seat and tapers down to meet the rubber membrane of the urine canister.

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The rubber membrane is replaceable and works to keep liquid waste odor from escaping.

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The urine container has a capacity of 1.2 gallons and also comes with a solid lid to prevent leakage while transporting it for emptying.

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The solid waste container has a capacity of 1.6 gallons, enough for about six to eight “number twos”. You can use one waste bag for a few days and only empty it once full, but the more you empty it, the less odors will have a chance to develop.

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The exterior body of the EVO is water resistant so it can be used in shower areas if needed.

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If you look closely at the bottom of the EVO’s body, you’ll notice icons indicating spots for the waste containers.

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Both the urine and solid waste containers fit snugly inside of the EVO body along with their lids.

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Assembly, Installation, Setup

The only assembly required for the Trelino EVO portable composting toilet is making sure all of the components are in their correct spots and a waste bag is in place with a bit of litter.

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The included waste bags are pretty big and have two long handles, making it easy to tie them off for disposal.

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Because the bags are so large, it’s easy to fold them over the top of the solids container to prevent any leakage.

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It’s wise to put in a few initial scoops of litter at the bottom of the bag once it’s in place.

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Suggested litter mediums are sawdust, coconut coir, organic peat moss, soil, or dried coffee grounds. I used inexpensive cat litter, assuming it would work well, considering that this is essentially what it was designed for.

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With the litter in place, put both containers into the EVO’s body and make sure they sit correctly.

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Pop the seat on and you’re all ready to “go”.

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During testing, the EVO S performed remarkably well. After 8-10 uses I never smelled anything but the faint aroma of cat litter. For the best results, it’s very important to put at least two scoops of litter on top of your waste after each use.

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One issue I found is that even though the seat is designed to keep solid and liquid wasted separated, human biology doesn’t always comply. It does take some deliberate effort to keep liquid waste out of the solids areas and vice versa.

The seat was comfortable, but definitely not designed for larger bottoms. That being said, it’s quite usable and much better than no seat at all.

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Some users reported that the included biodegradable waste bags degraded much too quickly, but I found that they worked well. I purposely left the test waste in the bag for over a week and the bag held up like a champ. It may have been that I used a lot of litter as per the instructions, to continually dry out the solid waste.

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Emptying the EVO was pretty simple, the waste bags tie off easily and the handle on the urine container makes removing it a breeze. The flat top and sides of the container do make it a little difficult to empty every drop, but it wasn’t really an issue. Hopefully future versions will have a more tapered top to help the liquid drain out easier.

What I like about the Trelino Evo S Composting Toilet

  • Very compact and simple design
  • Innovative system for separating waste to reduce odors
  • Easy and discreet method for emptying waste

What needs to be improved

  • Takes deliberate effort at times to keep solid and liquid waste separate during use
  • EVO S might be too small for some users and scenarios
  • Quite expensive

Final thoughts

The Trelino Evo S Composting Toilet is an excellent choice for many travel scenarios. While the small version (S) might not be the best fit for larger users such as myself, Trelino does offer medium (M) and large versions (L) of the EVO. The design, functionality, and ease of use of the EVO are outstanding. The included waste bags reportedly degrade a bit too quickly, but after extensive testing, I found that they work perfectly fine. Just in case, there are plenty of other affordable bag options on the market. The innovative waste separation, combined with the use of a good litter medium, seriously reduces and practically eliminates odors, especially when the unit is emptied often. The Trelino packs down into a simple, nondescript box, which makes it easy to fit in with other gear when space is at a premium. At $399, the price is a bit high for what’s basically a human litter box, but I believe it’s worth it due to the Trelino EVO’s great design, features, and portability.

Price: $375.00
Where to buy: Trelino and Amazon
Source: The sample of this product was provided for free by Trelino. Trelino did not have a final say on the review and did not preview the review before it was published.

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